1. Field of the Invention
The invention relates to a set of piston pumps, in particular fuel pumps for internal combustion engines with direct fuel injection, each having one drive region and at least one pumping region.
The subject of the invention is also a piston pump, in particular a fuel pump for internal combustion engines with direct fuel injection, having one drive region and at least one pumping region.
2. Description of the Prior Art
Piston pumps of the type with which this invention is concerned are known, for instance from German Patent Disclosure DE 199 07 311 A1 which discloses hydraulic pumps with a drive housing in which a drive shaft is supported. As a result, a drive region of the hydraulic pump is formed. A piston is located radially to the axis of the drive shaft and is received in a cylinder bush in a way capable of reciprocation. The reciprocation is forced on the piston by cams of the drive shaft. A cylinder head with an inlet valve and an outlet valve is secured to the drive housing. A piston, cylinder bush, cylinder head, inlet valve and outlet valve, and other components form a pumping region of the hydraulic pump, because in the final analysis it is through this region that the fuel is pumped. The known piston pump is a two-cylinder radial piston pump. This defines the design of the known piston pump.
It is the object of the invention to reduce the production costs of piston pumps and expand their range of application.
This object is attained, in a set of piston pumps of the type defined at the outset, in that the set of piston pumps includes at least two piston pumps of different design, and the pumping regions of all the piston pumps of the set are embodied as structurally identical pumping modules.